中国物理B ›› 2015, Vol. 24 ›› Issue (7): 75204-075204.doi: 10.1088/1674-1056/24/7/075204

• PHYSICS OF GASES, PLASMAS, AND ELECTRIC DISCHARGES • 上一篇    下一篇

Modeling of the nanoparticle coagulation in pulsed radio-frequency capacitively coupled C2H2 discharges

刘相梅, 李奇楠, 李瑞   

  1. School of Science, Qiqihar University, Qiqihar 161006, China
  • 收稿日期:2014-11-17 修回日期:2015-01-09 出版日期:2015-07-05 发布日期:2015-07-05
  • 基金资助:
    Project supported by the Natural Science Foundation of Heilongjiang Province, China (Grant Nos. A2015011 and A2015010), the Postdoctoral Scientific Research Developmental Fund of Heilongjiang Province, China (Grant No. LBH-Q14159), the National Natural Science Foundation of China (Grant No. 11404180), and the Program for Young Teachers Scientific Research in Qiqihar University, China (Grant No. 2014k-Z11).

Modeling of the nanoparticle coagulation in pulsed radio-frequency capacitively coupled C2H2 discharges

Liu Xiang-Mei (刘相梅), Li Qi-Nan (李奇楠), Li Rui (李瑞)   

  1. School of Science, Qiqihar University, Qiqihar 161006, China
  • Received:2014-11-17 Revised:2015-01-09 Online:2015-07-05 Published:2015-07-05
  • Contact: Liu Xiang-Mei E-mail:lxmjsc98@163.com
  • Supported by:
    Project supported by the Natural Science Foundation of Heilongjiang Province, China (Grant Nos. A2015011 and A2015010), the Postdoctoral Scientific Research Developmental Fund of Heilongjiang Province, China (Grant No. LBH-Q14159), the National Natural Science Foundation of China (Grant No. 11404180), and the Program for Young Teachers Scientific Research in Qiqihar University, China (Grant No. 2014k-Z11).

摘要: The role of pulse parameters on nanoparticle property is investigated self-consistently based on a couple of fluid model and aerosol dynamics model in a capacitively coupled parallel-plate acetylene (C2H2) discharge. In this model, the mass continuity equation, momentum balance equation, and energy balance equation for neutral gas are taken into account. Thus, the thermophoretic force arises when a gas temperature gradient exists. The typical results of this model are positive and negative ion densities, electron impact collisions rates, nanoparticle density, and charge distributions. The simulation is performed for duty ratio 0.4/0.7/1.0, as well as pulse modulation frequency from 40 kHz to 2.7 MHz for pure C2H2 discharges at a pressure of 500 mTorr. We find that the pulse parameters, especially the duty ratio, have a great affect on the dissociative attachment coefficient and the negative density. More importantly, by decreasing the duty ratio, nanoparticles start to diffuse to the wall. Under the action of gas flow, nanoparticle density peak is created in front of the pulse electrode, where the gas temperature is smaller.

关键词: nanoparticle coagulation, pulsed radio-frequency capacitively coupled acetylene discharges

Abstract: The role of pulse parameters on nanoparticle property is investigated self-consistently based on a couple of fluid model and aerosol dynamics model in a capacitively coupled parallel-plate acetylene (C2H2) discharge. In this model, the mass continuity equation, momentum balance equation, and energy balance equation for neutral gas are taken into account. Thus, the thermophoretic force arises when a gas temperature gradient exists. The typical results of this model are positive and negative ion densities, electron impact collisions rates, nanoparticle density, and charge distributions. The simulation is performed for duty ratio 0.4/0.7/1.0, as well as pulse modulation frequency from 40 kHz to 2.7 MHz for pure C2H2 discharges at a pressure of 500 mTorr. We find that the pulse parameters, especially the duty ratio, have a great affect on the dissociative attachment coefficient and the negative density. More importantly, by decreasing the duty ratio, nanoparticles start to diffuse to the wall. Under the action of gas flow, nanoparticle density peak is created in front of the pulse electrode, where the gas temperature is smaller.

Key words: nanoparticle coagulation, pulsed radio-frequency capacitively coupled acetylene discharges

中图分类号:  (Plasma simulation)

  • 52.65.-y
52.27.Lw (Dusty or complex plasmas; plasma crystals) 52.80.Pi (High-frequency and RF discharges)